1. Field of Invention
The present invention relates generally to weight-lifting apparatus and a method of assembling the apparatus, and more particularly to fixed dumbbells and barbells and a method of assembling to insure the user's safety after the apparatus has undergone heavy commercial use.
2. Description of the Prior Art
Fixed dumbbells and barbells are those in which the individual weights or heads cannot be added or subtracted by the user, but are permanently fixed to each end of a handle or bar. Fixed dumbbells and barbells have been used for over 50 years in commercial exercise environments such as health clubs, gyms, schools, YMCAs and the like. Under such heavy commercial use, the heads on the fixed dumbbells and barbells become loose on the handle causing the heads to rotate. The moment the heads begin to loosen, the user has insecurities concerning the safety of the equipment. The goal in assembling such weight-lifting equipment is to prevent the heads from becoming loose.
Patti, U.S. Pat. No. 6,602,169 (the '169 Patent), offered a solution to the foregoing problem by disclosing and claiming a method for placing a single locking nut on threaded ends of the handle.
It has been found that even with the improvement offered in the '169 Patent, the problem of rotation still exists. There is a need for improvements in dumbbell and barbell design to eliminate such rotation.